" A PROCESS FOR THE PREPARATION OF THE DELTA-CRYSTALLINE FORM OF IVABRADINE HYDROCHLORIDE "

Abstract

Process for the preparation of the &#948;-crystalline form of ivabradine hydrochloride, wherein acetonitrile or a mixture of acetonitrile and water is preheated, ivabradine hydrochloride is added, the solution obtained is allowed to cool at room temperature, held at room temperature until crystallisation is complete, and the crystals formed are collected.

Full Text

The present invention relates to the 6-crystalline form of ivabradine hydrochloride of formula (I)
(Formula Removed)
to a process for its preparation and to pharmaceutical compositions containing it.
Ivabradine, and addition salts thereof with a pharmaceutically acceptable acid, and more especially its hydrochloride, have very valuable pharmacological and therapeutic properties, especially bradycardic properties, making those compounds useful in the treatment or prevention of various clinical situations of myocardial ischaemia such as angina pectoris, myocardial infarct and associated rhythm disturbances, and also in various pathologies involving rhythm disturbances, especially supraventricular rhythm disturbances, and in heart failure.
The preparation and therapeutic use of ivabradine and addition salts thereof with a pharmaceutically acceptable acid, and more especially its hydrochloride, have been described in the European patent specification EP 0 534 859.
In view of the pharmaceutical value of this compound, it has been of prime importance to obtain it with excellent purity. It has also been important to be able to synthesise it by means of a process that can readily be converted to the industrial scale, especially in a form that allows rapid filtration and drying. Finally, that form had to be perfectly reproducible, easily formulated and sufficiently stable to allow its storage for long periods without particular requirements for temperature, light or oxygen level.
The patent specification EP 0 534 859 describes a synthesis process for ivabradine and its hydrochloride. However, that document does not specify the conditions for obtaining ivabradine in a form that exhibits those characteristics in a reproducible manner.
The Applicant has now found that a particular salt of ivabradine, the hydrochloride, can be obtained in a well defined crystalline form that exhibits valuable characteristics for stability and processability.
More specifically, the present invention relates to the 8-crystalline form of ivabradine hydrochloride, characterised by the following powder X-ray diffraction diagram, measured using a PANalytical X'Pert Pro diffractometer together with an X'Celerator detector and expressed in terms of line position (Bragg's angle 2 theta, expressed in degrees), line height (expressed in counts), line area (expressed in counts x degrees), line width at half-height ("FWHM", expressed in degrees) and interplanar distance d (expressed in A):
(Table Removed)
The invention relates also to a process for the preparation of the 6-crystalline form of ivabradine hydrochloride, which process is characterised in that acetonitrile or a mixture of acetonitrile and water is preheated, ivabradine hydrochloride is added, the solution obtained is allowed to cool at room temperature, held at room temperature until crystallisation is complete, and the crystals formed are collected.
• In the crystallisation process according to the invention it is possible to use
ivabradine hydrochloride obtained by any process, for example ivabradine
hydrochloride obtained by the preparation process described in patent specification
EP 0 534 859.
• The solution may advantageously be seeded during the cooling step.
• The acetonitrile or mixture of acetonitrile and water is preferably preheated to a temperature between 60°C and reflux, more preferably between 65 and 75°C.
• The dilution is preferably more than 15 ml/g, more preferably between 50 and 100
ml/g.
The invention relates also to pharmaceutical compositions comprising as active ingredient the δ-crystalline form of ivabradine hydrochloride together with one or more appropriate, inert and non-toxic excipients. Among the pharmaceutical compositions according to the invention there may be mentioned, more especially, those that are suitable for oral, parenteral (intravenous or subcutaneous) or nasal administration, tablets or dragees, sublingual tablets, capsules, lozenges, suppositories, creams, ointments, dermal gels, injectable preparations and drinkable suspensions.
The useful dosage can be varied according to the nature and severity of the disorder, the administration route and the age and weight of the patient. The dosage varies from 1 to 500 mg per day in one or more administrations.
The Examples that follow illustrate the invention.
The X-ray powder diffraction spectrum was measured under the following experimental conditions :
PANalytical X'Pert Pro diffractometer, X'Celerator detector, temperature-regulated
chamber,
voltage 45 kV, intensity 40 mA,
mounting 6-d,
nickel (Kß) filter,
incident-beam and diffracted-beamSoller slit: 0.04 rad,
automatic divergence slits : irradiated length of 10 mm,
mask: 10 mm,
antiscatter slit: 1/2°,
measurement mode : continuous from 3° to 30°, in increments of 0.017°,
measurement time per step : 19.7 s,
total time : 4 min 32 s,
- measurement speed : 0.108°/s,
- measurement temperature : ambient.
EXAMPLE 1 : δ-crystalline form of ivabradine hydrochloride
160 ml of acetonitrile are preheated to 70°C and then 2 g of ivabradine hydrochloride obtained according to the process described in patent specification EP 0 534 859 are added, in portions, with stirring until dissolution is complete. The solution is then stored at ambient temperature for 2 days. The crystals are removed by filtration in vacuo and are spread out onto a crystallisation plate.
The water content of the product obtained, determined by coulometry, is 2.8 %.
Powder X-ray diffraction diagram :
The powder X-ray diffraction profile (diffraction angles) of the 5-form of ivabradine hydrochloride is given by the significant lines collated in the following table:
(Table Removed)
EXAMPLE 2 : Pharmaceutical composition
Formula for the preparation of 1000 tablets each containing 5 mg of ivabradine base:
Compound of Example 1 5.39 g
Maize starch 20 g
Anhydrous colloidal silica 0.2 g
Mannitol 63.91 g
PVP 10 g
Magnesium stearate 0.5 g

WE CLAIM
1. Process for the preparation of the 8-crystalline form of ivabradine hydrochloride, wherein
acetonitrile or a mixture of acetonitrile and water is preheated, ivabradine hydrochloride
is added, the solution obtained is allowed to cool at room temperature, held at room
temperature until crystallisation is complete, and the crystals formed are collected.
2. Process as claimed in claim 1, wherein the solution of ivabradine hydrochloride is seeded during the cooling step.